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Palaeohystrichophora myalupensis
Palaeohystrichophora "myalupensis" Churchill and Sarjeant, 1962, p.38–40, figs.5,22–23.
NOW Cobricosphaeridium (Acritarch). Originally Palaeohystrichophora, subsequently Aquadulcum (Acritarch), thirdly (and now) Cobricosphaeridium (Acritarch).
Holotype: Churchill and Sarjeant, 1962, figs.5,22.
Age: Holocene.
Original diagnosis: Churchill and Sarjeant, 1962, p.38
A species of Palaeohystrichophora having an ellipsoidal shell: the epitheca, which is considerably larger than the hypotheca, has the form of a rounded cone, the hypotheca is almost hemispherical. Transverse furrow not, or only very slightly, spiral, very broad: longitudinal furrow of moderate breadth, extending from apex to antapex. The shell surface bears an irregular scatter of short spines, simple or with two unequally developed branches: spines are few or absent on the furrows.
Original description: Churchill and Sarjeant, 1962, p.38-39
Shell pale yellowish, minutely granular. Transverse furrow slightly sunken, longitudinal furrow apparently not sunken. The spines vary in length and are most often simple: they are typically absent from the furrows, but sometimes, as in the holotype, a very few spines are present on the transverse furrow. This probably indicates that the furrows were function-less and that the shells are cysts, and not motile individuals.
Dimensions:
Holotype: length of shell 51 µm, breadth 37 µm, length of spines (max.) 3.5 µm. Observed range: length 48-55 µm.
Affinities:
Churchill and Sarjeant, 1962, p.39-40: Palaeohystrichophora myalupense differs from all described species in shape, breadth of transverse furrow and nature of spine cover. The most comparable species is Palaeohystrichophora minuta Deflandre and Cookson 1955, from the Senonian of Western Australia, which differs, however, in its more distinctly biconical shape, with a truncate apical process and pointed antapex.
NOW Cobricosphaeridium (Acritarch). Originally Palaeohystrichophora, subsequently Aquadulcum (Acritarch), thirdly (and now) Cobricosphaeridium (Acritarch).
Holotype: Churchill and Sarjeant, 1962, figs.5,22.
Age: Holocene.
Original diagnosis: Churchill and Sarjeant, 1962, p.38
A species of Palaeohystrichophora having an ellipsoidal shell: the epitheca, which is considerably larger than the hypotheca, has the form of a rounded cone, the hypotheca is almost hemispherical. Transverse furrow not, or only very slightly, spiral, very broad: longitudinal furrow of moderate breadth, extending from apex to antapex. The shell surface bears an irregular scatter of short spines, simple or with two unequally developed branches: spines are few or absent on the furrows.
Original description: Churchill and Sarjeant, 1962, p.38-39
Shell pale yellowish, minutely granular. Transverse furrow slightly sunken, longitudinal furrow apparently not sunken. The spines vary in length and are most often simple: they are typically absent from the furrows, but sometimes, as in the holotype, a very few spines are present on the transverse furrow. This probably indicates that the furrows were function-less and that the shells are cysts, and not motile individuals.
Dimensions:
Holotype: length of shell 51 µm, breadth 37 µm, length of spines (max.) 3.5 µm. Observed range: length 48-55 µm.
Affinities:
Churchill and Sarjeant, 1962, p.39-40: Palaeohystrichophora myalupense differs from all described species in shape, breadth of transverse furrow and nature of spine cover. The most comparable species is Palaeohystrichophora minuta Deflandre and Cookson 1955, from the Senonian of Western Australia, which differs, however, in its more distinctly biconical shape, with a truncate apical process and pointed antapex.